On "The Early Show," CBS News Medical Correspondent Dr. Jennifer Ashton explained the survey looked at over 30,000 kids and found, on average, kids are snacking at least three times a day -- adding almost 600 calories from snacks alone, up 168 calories from the late '70s.
"Snacking sometimes takes the place of mealtime, leaving kids less hungry for nutritious foods," Ashton said.
She said researchers found kids are loading up on high calorie junk food. Salty snacks, such as chips and crackers, showed the largest increase.
"Kids are eating more candy at snack time, leading to weight gain and cavities," Ashton said. "Kids are less likely to drink milk, instead reaching for soda and sports drinks. Cookies and cakes were also popular."
And the extra snacking can really pack on the pounds.
Ashton said, "It boils down to the numbers: if 3,500 calories consumed equals 1 pound. If, as the study found, kids are eating on average an extra 168 calories a day, that could add up to a 17.5 pound weight gain in one year. No small matter."
And those extra pounds are very dangerous, according to Ashton, who cited that the rise in childhood obesity has put millions of children at risk of chronic conditions, such as high blood pressure, diabetes and even heart disease.
Ashton added that a study released this week showed that obese children as young as 3 years old showed biomarkers considered an early warning sign for heart disease.
She continued, "A report out in 2005 said that childhood obesity, if left unchecked, could shorten life spans by as much as five years, and they would have shorter life expectancies than their parents."
What can parents do?
Ashton said parents and children need to work together -- but it can be challenging.
She said, "Vending machines are everywhere stocked with junk, and the food industry seduces kids with tempting snack foods. But parents need to set an example by making healthy choices themselves. Interestingly, young children, ages 2 to 6, have shown the biggest increases in snacking. Young children cannot buy the food themselves, or drive themselves to fast food restaurants. Parents need to supply good snack choices."
Ashton suggested these healthy snack alternatives that kids will actually want to eat:
• Keep cut fruit in the lunch box and in the fridge. You could even swipe some peanut butter on it.
• Keep baby carrots and sweet peppers. Cut them up, dip them in low-fat dip.
• Yogurt is great, top them with raisins.
• No-butter popcorn is low in calories and filling too.
• If your child is not allergic, nuts are a great option for protein and good fats.